I have an iPad Pro 12.9” 4th generation. I want to save files from it to an external HD. I am looking for advice as to which brand external hard drives work best with this iPad. Thanks.
iPad Pro, iPadOS 15
An SSD may be a better choice for bulk storage - as these are both more robust and require considerably less power.
You should also understand that Hard Disk Drives (HDD) are notoriously power-hungry. Depending upon your iPad model, unless your external HDD has its own source of power, you will very likely need to use either a powered USB hub - or for models that incorporate a Lightning connector, use an Apple Lightning to USB3 Camera Adapter to which you must also connect your iPad Power Adapter. When using the Camera Adapter, the connected Power Adapter must be rated at least 12W (2.4A @5V) - although a 20-30W Power Adapter is recommended.
https://store.apple.com/uk/xc/product/MK0W2ZM/A
If you have one of the newer iPad or iPad Pro models, with a USB-C connector, you may need to utilise a powered USB hub (i.e., it has its own source of power) - connecting both the iPad Pro and the storage device to ports on the hub.
Some additional information can be found here:
Connect external devices or servers with Files on iPhone - Apple Support
https://www.imore.com/how-use-external-hard-drives-your-iphone-or-ipad
To be recognised by iPadOS, the attached USB storage device must be formatted to FAT, FAT32, exFAT, APFS or HFS+ with a single partition. Microsoft NTFS is not supported. Formatting and partitioning, if required, must be performed using a separate computer; iPad does not provide any facilities to format an external storage device.
Beyond these considerations, most brands of storage device are likely to be suitable - although using good quality storage devices from mainstream manufacturers is recommended.
An SSD may be a better choice for bulk storage - as these are both more robust and require considerably less power.
You should also understand that Hard Disk Drives (HDD) are notoriously power-hungry. Depending upon your iPad model, unless your external HDD has its own source of power, you will very likely need to use either a powered USB hub - or for models that incorporate a Lightning connector, use an Apple Lightning to USB3 Camera Adapter to which you must also connect your iPad Power Adapter. When using the Camera Adapter, the connected Power Adapter must be rated at least 12W (2.4A @5V) - although a 20-30W Power Adapter is recommended.
https://store.apple.com/uk/xc/product/MK0W2ZM/A
If you have one of the newer iPad or iPad Pro models, with a USB-C connector, you may need to utilise a powered USB hub (i.e., it has its own source of power) - connecting both the iPad Pro and the storage device to ports on the hub.
Some additional information can be found here:
Connect external devices or servers with Files on iPhone - Apple Support
https://www.imore.com/how-use-external-hard-drives-your-iphone-or-ipad
To be recognised by iPadOS, the attached USB storage device must be formatted to FAT, FAT32, exFAT, APFS or HFS+ with a single partition. Microsoft NTFS is not supported. Formatting and partitioning, if required, must be performed using a separate computer; iPad does not provide any facilities to format an external storage device.
Beyond these considerations, most brands of storage device are likely to be suitable - although using good quality storage devices from mainstream manufacturers is recommended.
Pretty much any brand should work. Adata, Kingston, SandDisk and Samsung are good SSD brands to look for.
Best External HD for my 4th gen iPad Pro 12.9”
